What is the recommended treatment for a generally healthy adult with strep throat?

Treatment of Strep Throat in Adults

For a generally healthy adult with strep throat, penicillin V 500 mg orally twice daily for 10 days or amoxicillin 500 mg orally twice daily for 10 days is the recommended first-line treatment. 1, 2

First-Line Treatment for Non-Allergic Patients

Penicillin or amoxicillin remains the drug of choice due to proven efficacy, narrow spectrum, safety, and low cost, with no documented penicillin resistance in Group A Streptococcus anywhere in the world. 1, 2

• Penicillin V 500 mg orally twice daily for 10 days is the standard regimen 1, 2
• Amoxicillin 500 mg orally twice daily for 10 days is equally effective and more palatable 1, 3
• Benzathine penicillin G 1.2 million units intramuscularly as a single dose can be used for patients unlikely to complete oral therapy 1, 2

The twice-daily dosing of penicillin is as efficacious as more frequent dosing regimens and significantly improves compliance 4. Once-daily penicillin is associated with decreased efficacy and should not be used, though once-daily amoxicillin has been shown to be effective 1, 4.

Critical Treatment Duration

A full 10-day course is essential to achieve maximal pharyngeal eradication of Group A Streptococcus and prevent acute rheumatic fever. 5, 1, 2

• Shortening the course below 10 days dramatically increases treatment failure rates and rheumatic fever risk 1, 2
• The only exception is azithromycin, which requires only 5 days due to its prolonged tissue half-life 1, 6
• Therapy can be safely postponed up to 9 days after symptom onset and still prevent acute rheumatic fever 6

Treatment for Penicillin-Allergic Patients

The choice of alternative antibiotic depends critically on the type of penicillin allergy:

Non-Anaphylactic Penicillin Allergy

First-generation cephalosporins are the preferred first-line alternatives with strong, high-quality evidence. 1, 6, 2

• Cephalexin 500 mg orally twice daily for 10 days 1, 6, 2
• Cefadroxil 1 gram orally once daily for 10 days 1, 6
• Cross-reactivity risk is only 0.1% in patients with non-severe, delayed penicillin reactions 6, 2

Immediate/Anaphylactic Penicillin Allergy

Clindamycin is the preferred choice for patients with immediate hypersensitivity reactions to penicillin. 1, 6, 2

• Clindamycin 300 mg orally three times daily for 10 days 1, 6, 2
• Approximately 1% resistance rate among Group A Streptococcus in the United States 1, 6
• Demonstrates high efficacy even in chronic carriers who have failed penicillin treatment 1, 6, 2
• Patients with immediate hypersensitivity must avoid all beta-lactam antibiotics, including cephalosporins, due to up to 10% cross-reactivity risk 1, 6, 2

Alternative Macrolides (Less Preferred)

• Azithromycin 500 mg orally once daily for 5 days 1, 6
• Clarithromycin 250 mg orally twice daily for 10 days 1, 6
• Macrolide resistance is 5-8% in the United States and varies geographically, making clindamycin more reliable 1, 6, 2

Adjunctive Symptomatic Treatment

• Acetaminophen or NSAIDs (such as ibuprofen) for moderate to severe symptoms or high fever 1, 6, 2
• Aspirin must be avoided in children due to Reye syndrome risk 1, 6, 2
• Corticosteroids are not recommended 1, 6

Common Pitfalls to Avoid

Do not shorten the antibiotic course below 10 days (except azithromycin's 5-day regimen), as this increases treatment failure and rheumatic fever risk. 1, 2

• Do not use cephalosporins in patients with immediate/anaphylactic penicillin reactions due to 10% cross-reactivity 1, 6, 2
• Do not prescribe broad-spectrum cephalosporins (cefdinir, cefixime, cefpodoxime) when narrow-spectrum first-generation agents are appropriate 6
• Do not use tetracyclines, sulfonamides, or fluoroquinolones due to high resistance rates 1
• Do not assume all penicillin-allergic patients need macrolides—first determine the type of allergy 6, 2

Special Considerations for Treatment Failures

For patients who have failed initial therapy, clindamycin demonstrates superior eradication rates in treatment failures and chronic carriers. 6

• Clindamycin 300 mg orally three times daily for 10 days 6
• Amoxicillin-clavulanate 40 mg amoxicillin/kg/day in 3 doses (max 2000 mg/day) for 10 days 6
• Consider that the patient may be a chronic carrier experiencing repeated viral infections rather than true recurrent strep infections 6, 2
• Chronic carriers generally do not require treatment unless special circumstances exist 6, 2

Follow-Up and Monitoring

• Routine post-treatment throat cultures or rapid antigen tests are not recommended for asymptomatic patients who have completed therapy 1, 2
• Patients with worsening symptoms after appropriate antibiotic initiation or with symptoms lasting 5 days after the start of treatment should be reevaluated 7